1. Field of the Invention
The invention relates to a bone harvesting device for collecting bone tissue that can be used in orthopedic procedures.
2. Description of the Related Art
Many orthopedic procedures require bone tissue to be harvested at one location on a patient for use at another location on the patient. For example, some patients experience a deterioration of the discs between vertebrae due to disease or injury. The deterioration of the discs causes the vertebrae to impinge upon nerves in and near the spine. The condition is extremely painful and debilitating. One procedure for addressing this problem is to fuse vertebrae together on opposite sides of the damaged disc. Spinal fusion surgery may include implantation of harvested bone tissue in the region between the vertebrae that are to be fused.
Bone tissue also may be harvested from one location to help heal a broken bone at a different location. For example, a severe fracture may completely sever a bone and may produce bone fragments in areas near the fracture. A severe break of this type often requires surgical intervention to remove some of the bone fragments. Additionally, a plate or rod may be implanted to provide structural support for the broken bone. Bone tissue harvested from one location may be implanted across the fracture and adjacent to the bone plate or rod. The harvested bone tissue will regenerate and contribute to structural support across the fracture.
Many patients experience disease or injury at joints. Diseased or damaged joints may require implantation of a prosthetic joint to supplement a portion of the diseased or damaged natural joint or to completely replace the natural joint. For example, total hip replacement requires the head of the natural femur to be removed and replaced by a prosthetic component. The prosthetic component includes a stem that must be inserted into a hole bored in the intramedullary cavity of the femur. Harvested bone tissue may be implanted around the stem of the femoral component of the prosthetic joint to enhance the support of the joint in the natural femur. Similarly, a socket may be implanted in a cavity prepared in the hip of the patient. Harvested bone tissue may be implanted around the prosthetic socket to provide the necessary support for the socket.
Many tools and techniques are employed for harvesting bone tissue. For example, some surgeons employ a reamer that is structurally and functionally similar to a cheese grater. The reamer may be generally cylindrical or spherical and may be formed from a thin stainless steel material. A plurality of openings are formed through the wall of the reamer and at least one side of each opening is sharpened and bulged to define a cutting edge that can cut into the bone tissue. The reamer is rubbed against or rotated against a targeted area for bone harvesting. As a result, bone tissue is cut from the bone and accumulates inside the reamer. The surgeon then must collect the accumulated bone tissue from the inside of the reamer in much the same way that grated cheese is accumulated from the inside of a cheese grater. Some reamers have worked well. However, it often is difficult to precisely target a location from which bone will be harvested with a reamer. Additionally, it is difficult for a surgeon to accurately determine how much bone tissue has been harvested. In some instances, too much bone tissue is accumulated in the reamer, thereby creating unnecessary trauma at the site of the bone harvesting. In other instances, too little bone tissue is harvested and the surgeon must revisit the site of the harvesting to collect additional tissue.
Some surgeons employ an auger-type tool to bore a hole in the bone at the site where the bone tissue is to be harvested. The auger is a rotating tool that produces bone debris in much the same way that a conventional drill produces sawdust when drilling into a piece of wood. This bone harvesting technique also requires the surgeon to guess about the volume of bone tissue that is being collected. Furthermore, the harvested bone tissue is not collected conveniently by the anger.
In view of the above, it is an object of the subject invention to provide a tool for harvesting bone tissue from specified locations and in clearly definable amounts.
It is another object of the subject invention to provide a bone harvesting tool that can be utilized easily by a surgeon.